Mr. Brown said Friday he is sending envoys to several allied nations to persuade them to reaffirm their commitment to the eight-year war by deploying more troops. His comments on BBC Radio, coming weeks before Mr. Obama is expected to announce his plans, could help reinvigorate NATO commitment to Afghanistan.

"I believe I can persuade countries, who said only a few weeks ago they would send no more troops to Afghanistan, that if we are training Afghan forces and partnering, and if there is a way forward that allows troops to come home over time, it's right for them to contribute troops as well," Brown said, adding, "And so burden-sharing will happen."

There are 58,000 US troops and 39,000 allied forces in Afghanistan. Britain has the second-largest force there after the US, with 9,000 troops.

Brown's comments came after the US ambassador to Afghanistan, Karl Eikenberry, expressed strong reservations to the White House about committing more American forces amid deepening fears that the government of President Hamid Karzai was too corrupt to be a reliable partner in the war. The comments, expressed in two classified cables leaked to the Washington Post, have shaken the resolve of some American officials, in that they come from an ambassador and former military commander who knows Afghanistan well.

An uptick in NATO support?

Many European nations have been reluctant to commit to more troops to Afghanistan, given waning support for the war in their own countries and the absence of a decision from Obama. But some officials say that may be changing as Obama's decision time grows near.

"There's very definitely an expectation of a substantial contribution coming from NATO," says an American diplomat in Europe.

"All nations should re-examine what further resources they could make available in terms of military, financial, or civilian contributions to help the Afghans take an increasing lead in managing their own affairs," Mr. Rasmussen said Nov. 6.

Also, the German defense minister recently made a significant rhetorical shift by calling the Afghan mission "warlike" for the first time, say US officials.

Germany, which is the third largest contributor of forces to Afghanistan with about 4,500 troops, has long been criticized for confining its mission largely to training Afghan forces and leaving most combat-related missions to other forces.

On Friday, Germany said it would send 120 more combat-troops in January to reinforce a rapid-reaction unit there.

"I think that this is the only place where something can give at this point," she says.

Waiting for Obama's decision

Obama is reportedly still dissatisfied with the strategic options before him, which range from a smaller commitment of between 10,000 and 15,000 troops to a larger one, favored by his generals, of 40,000 troops.

Last week, the Pentagon's top policy official, Michèle Flournoy, and other uniformed officials met with military leaders in Europe in an unannounced meeting designed to "hold ground" there as the Obama administration finishes its deliberations on the war strategy. It appears that European leaders are more receptive to the Obama administration's requests for help than the previous White House, which had alienated some NATO countries.

When Obama's decision comes – most likely after his ongoing week-long Asia trip – the international community may be more willing to follow suit. "This is classic high-stakes poker right now," says the US diplomat in Europe.